In New Zealand, as in other developed nations, community-led conservation groups work to maintain and restore ecosystems and conserve indigenous biodiversity. These groups receive support in the form of materials, technical advice and funding from central and local government and non-governmental organisations, who are required increasingly to demonstrate delivery of benefits or conservation returns on investments. However, there is little empirical evidence for the objective evaluation of the effectiveness of community-based programmes in achieving national conservation outcomes.
Mesopredator and competitor release can lead to population increases of invasive house mice (Mus musculus) after larger introduced mammals are controlled or eradicated. In New Zealand, mammal-resistant fences have enabled multi-species mammal eradications in order to protect indigenous species. When house mice are the only mammals remaining in these biodiversity sanctuaries, they may reach a high population density, with potential consequences for their indigenous prey.
Abstract: The Department of Conservation has implemented a Biodiversity and Monitoring Reporting System (BMRS) that estimates occupancy rates and relative abundances of introduced brushtail possums (Trichosurus vulpecula) at a representative sample of sites on public conservation land. Leg-hold traps have been used to monitor possums in the BMRS, but wax tags and chew cards have logistical and financial advantages over traps.
This article assesses compliance with biodiversity compensation on New Zealand’s conservation land. Of the 261 Department of Conservation (DOC) concessions for commercial activity searched, only about 15% included compensation provisions. A sample of 20 concessions of that 15% suggests 68% achieve full compliance. Our results suggest compliance is influenced by factors such as habitat and activity type, protected area category, and whether a concession holder has pending concessions and/or renewals. Inconsistencies in compliance monitoring, enforcement, and reporting merit attention.
The endangered New Zealand sea lion (Phocarctos hookeri) has recently been confirmed as breeding on Stewart Island/Rakiura, southern New Zealand. This area is thought to have the largest number of sea lion pups born outside of the New Zealand subantarctics. However, the sparse distribution and cryptic behaviour of this population means known human threats and their effects on the population will be difficult to determine, limiting conservation priority setting and management.
There is a lack of information about how elevation affects the distribution of ship rats in New Zealand. In this study, ship rats (Rattus rattus) were captured in traps set along a 2 km elevational transect (455–1585 m a.s.l.) in beech (Nothofagaceae) forest and adjacent alpine tussock at Mt Misery, in Nelson Lakes National Park, from 1974 to 1993. A total of 118 rats were captured.
Introduced mammalian predators threaten populations of endemic New Zealand skinks. Their effects on skink populations have been not often quantified on the mainland and are known primarily from skink population increases on islands from which mammals have been eradicated. Estimating skink population density with capture–recapture trapping is time-consuming and costly. Counting skinks in artificial retreats in specific weather conditions may be a useful and relatively quick way to index population density, but needs calibration for different habitats and species.
The study of amphibian spatial behaviour provides key information for species conservation. Most commonly used techniques to track amphibians are either unsuitable for small species or fail to give sufficiently fine-resolution data of habitat use. We report on the use of non-toxic fluorescent powders to track the fine-scale movement of a threatened New Zealand frog, Leiopelma pakeka.
While invasive rats are demonstrably inimical to indigenous vertebrate species, there has not been unequivocal evidence of benefit to invertebrate communities from management of these invasive mammals in New Zealand forest systems. The present study examined the response of land snail communities to intensive management of ship and Norway rats by sampling paired rainforest blocks, one block of which had been subject to intensive management of rats, while the other block had been without management of invasive rats and thus subject to ambient rodent infestations.
In New Zealand, aerial poisoning with 1080 (sodium fluoroacetate) bait is widely used for control of introduced small mammal pests in remote or forested areas. However this practice is controversial, partly because of perceived risks to native fauna, particularly birds. That perception originally derives from substantial mortality of some native bird species in pre-1980 control operations, which prompted changes in baiting practice to mitigate most of the risk.